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type=\u0022text\/css\u0022 rel=\u0022stylesheet\u0022 href=\u0022https:\/\/jeb.biologists.org\/sites\/default\/files\/advagg_css\/css__KwIbTmK5u_TU0NIDnj2cXC8qhcT3ubSigju5zweyvGo__wfUCN1ftcRJqvO1mXYEDxSMyoCswJBppiBXHDPwtaqM__jcLkbSfAlXyhb-jQHVBRYf-pSjRDEvRHgFXJqxM9Wdo.css\u0022 media=\u0022all\u0022 \/\u003E\n\u003Clink rel=\u0027stylesheet\u0027 type=\u0027text\/css\u0027 href=\u0027\/sites\/all\/modules\/contrib\/panels\/plugins\/layouts\/onecol\/onecol.css\u0027 \/\u003E\u003C\/head\u003E\u003Cbody\u003E\u003Cdiv class=\u0022panels-ajax-tab-panel panels-ajax-tab-panel-jnl-template-cob-tab-data\u0022\u003E\u003Cdiv class=\u0022panel-display panel-1col clearfix\u0022 \u003E\n \u003Cdiv class=\u0022panel-panel panel-col\u0022\u003E\n \u003Cdiv\u003E\u003Cdiv class=\u0022panel-pane pane-cob-fragment-figures\u0022 \u003E\n \n \u003Ch2 class=\u0022pane-title\u0022\u003EArticle Figures \u0026amp; Tables\u003C\/h2\u003E\n \n \n \u003Cdiv class=\u0022pane-content\u0022\u003E\n \u003Cdiv class=\u0022elements-frag-data highwire-markup\u0022 id=\u0022fig-data\u0022\u003E\u003Cdiv id=\u0022fig-data-figures\u0022 class=\u0022group frag-figures\u0022\u003E\u003Cdiv class=\u0022fig-data-title-jump clearfix\u0022\u003E\u003Ch3 id=\u0022fig-frag-data-title\u0022 class=\u0022fig-data-group-title\u0022\u003EFigures\u003C\/h3\u003E\u003Cdiv class=\u0022fig-data-jump-links\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cdiv class=\u0022item-list\u0022\u003E\u003Cul id=\u0022fig-frag-fig\u0022 class=\u0022fig-frag-data-list clearfix\u0022\u003E\u003Cli class=\u0022first\u0022\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F1\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F1.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Schematized experimental setup for measuring a fly\u0027s response to image expansion. During tethered flight, the fly\u0027s wingstroke amplitude and frequency are measured by optically tracking the shadows cast from an infra-red (IR) diode by each of the wings on an optical wing-beat analyzer (Dickinson and Lighton, 1995; Lehmann and Dickinson, 1997). During closed-loop experiments, the difference between the amplitude of each wing stroke controls the visual display, allowing the fly to orient actively toward the position of the 15\u0026#xB0;\u0026#xD7;15\u0026#xB0; square. At periodic intervals, the square symmetrically expands, eliciting a behavioral response.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Schematized experimental setup for measuring a fly\u0027s response to image expansion. During tethered flight, the fly\u0027s wingstroke amplitude and frequency are measured by optically tracking the shadows cast from an infra-red (IR) diode by each of the wings on an optical wing-beat analyzer (Dickinson and Lighton, 1995; Lehmann and Dickinson, 1997). During closed-loop experiments, the difference between the amplitude of each wing stroke controls the visual display, allowing the fly to orient actively toward the position of the 15\u0026#xB0;\u0026#xD7;15\u0026#xB0; square. At periodic intervals, the square symmetrically expands, eliciting a behavioral response.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 1.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F1.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 1.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F1.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F1.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 1.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F1.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076113\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 1.\u003C\/span\u003E \n \u003Cp id=\u0022p-8\u0022\u003ESchematized experimental setup for measuring a fly\u0027s response to image\nexpansion. During tethered flight, the fly\u0027s wingstroke amplitude and\nfrequency are measured by optically tracking the shadows cast from an\ninfra-red (IR) diode by each of the wings on an optical wing-beat analyzer\n(\u003Ca id=\u0022xref-ref-9-3\u0022 class=\u0022xref-bibr\u0022 href=\u0022#ref-9\u0022\u003EDickinson and Lighton, 1995\u003C\/a\u003E;\n\u003Ca id=\u0022xref-ref-25-4\u0022 class=\u0022xref-bibr\u0022 href=\u0022#ref-25\u0022\u003ELehmann and Dickinson, 1997\u003C\/a\u003E).\nDuring closed-loop experiments, the difference between the amplitude of each\nwing stroke controls the visual display, allowing the fly to orient actively\ntoward the position of the 15\u00b0\u00d715\u00b0 square. At periodic\nintervals, the square symmetrically expands, eliciting a behavioral\nresponse.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F2\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F2.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Wing and leg responses elicited by an expanding object (recorded as V). In response to a square expanding at a rate of 500\u0026#xB0; s-1, the fly generates both wing and leg responses. The time course of stimulus expansion is shown in the bottom traces. If the object is displaced laterally, the inside wing (that on the side of the stimulus) shows a transient increase in wing-beat amplitude, while the outside wing decreases in stroke amplitude. (A) If the object is to the left of the fly, the left wing-beat amplitude (blue) increases while the right wing-stroke amplitude (red) decreases, causing the square to move to the rear of the fly\u0027s field of view. In contrast, expansion of centrally positioned objects elicits smaller changes in wing motion, causing little change in the position of the object (B). Image expansion in the frontal field of view elicits leg extension as well as an increase in wing-beat frequency, both indicative of a landing response. When the stimulus is to the right of fly, the sign of the change in both wing-beat responses is reversed, again causing the object to move to the rear of the fly\u0027s field of view (C). Laterally positioned image expansion elicits a transient increase in wing-beat frequency but does not evoke a leg response.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Wing and leg responses elicited by an expanding object (recorded as V). In response to a square expanding at a rate of 500\u0026#xB0; s-1, the fly generates both wing and leg responses. The time course of stimulus expansion is shown in the bottom traces. If the object is displaced laterally, the inside wing (that on the side of the stimulus) shows a transient increase in wing-beat amplitude, while the outside wing decreases in stroke amplitude. (A) If the object is to the left of the fly, the left wing-beat amplitude (blue) increases while the right wing-stroke amplitude (red) decreases, causing the square to move to the rear of the fly\u0027s field of view. In contrast, expansion of centrally positioned objects elicits smaller changes in wing motion, causing little change in the position of the object (B). Image expansion in the frontal field of view elicits leg extension as well as an increase in wing-beat frequency, both indicative of a landing response. When the stimulus is to the right of fly, the sign of the change in both wing-beat responses is reversed, again causing the object to move to the rear of the fly\u0027s field of view (C). Laterally positioned image expansion elicits a transient increase in wing-beat frequency but does not evoke a leg response.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 2.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F2.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 2.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F2.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F2.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 2.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F2.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076119\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 2.\u003C\/span\u003E \n \u003Cp id=\u0022p-14\u0022\u003EWing and leg responses elicited by an expanding object (recorded as V). In\nresponse to a square expanding at a rate of 500\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E, the fly\ngenerates both wing and leg responses. The time course of stimulus expansion\nis shown in the bottom traces. If the object is displaced laterally, the\ninside wing (that on the side of the stimulus) shows a transient increase in\nwing-beat amplitude, while the outside wing decreases in stroke amplitude. (A)\nIf the object is to the left of the fly, the left wing-beat amplitude (blue)\nincreases while the right wing-stroke amplitude (red) decreases, causing the\nsquare to move to the rear of the fly\u0027s field of view. In contrast, expansion\nof centrally positioned objects elicits smaller changes in wing motion,\ncausing little change in the position of the object (B). Image expansion in\nthe frontal field of view elicits leg extension as well as an increase in\nwing-beat frequency, both indicative of a landing response. When the stimulus\nis to the right of fly, the sign of the change in both wing-beat responses is\nreversed, again causing the object to move to the rear of the fly\u0027s field of\nview (C). Laterally positioned image expansion elicits a transient increase in\nwing-beat frequency but does not evoke a leg response.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F3\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F3.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022The effect of stimulus position on behavioral response. (A) A single fly\u0027s response to multiple presentations of a square expanding at 500\u0026#xB0; s-1 varies with stimulus position. Each individual trace shows the response of the left (blue) and right (red) wing to a presentation of the expansion stimulus. The bold and dotted lines represent the mean response\u0026#xB1; S.D. for stimuli between given positions. Expansion in lateral positions evokes the largest change in wing-beat amplitude (WBA), with responses decaying for more frontal and caudal stimulus presentations. (B) Results from multiple flies. The individual traces are the mean left and right wing-beat amplitude response taken from 12 individuals. The bold and dotted lines represent the mean \u0026#xB1; S.D., respectively, across individuals.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;The effect of stimulus position on behavioral response. (A) A single fly\u0027s response to multiple presentations of a square expanding at 500\u0026#xB0; s-1 varies with stimulus position. Each individual trace shows the response of the left (blue) and right (red) wing to a presentation of the expansion stimulus. The bold and dotted lines represent the mean response\u0026#xB1; S.D. for stimuli between given positions. Expansion in lateral positions evokes the largest change in wing-beat amplitude (WBA), with responses decaying for more frontal and caudal stimulus presentations. (B) Results from multiple flies. The individual traces are the mean left and right wing-beat amplitude response taken from 12 individuals. The bold and dotted lines represent the mean \u0026#xB1; S.D., respectively, across individuals.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 3.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F3.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 3.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F3.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F3.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 3.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F3.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076121\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 3.\u003C\/span\u003E \n \u003Cp id=\u0022p-17\u0022\u003EThe effect of stimulus position on behavioral response. (A) A single fly\u0027s\nresponse to multiple presentations of a square expanding at 500\u00b0\ns\u003Csup\u003E-1\u003C\/sup\u003E varies with stimulus position. Each individual trace shows the\nresponse of the left (blue) and right (red) wing to a presentation of the\nexpansion stimulus. The bold and dotted lines represent the mean response\u00b1\n S.D. for stimuli between given positions. Expansion in lateral\npositions evokes the largest change in wing-beat amplitude (WBA), with\nresponses decaying for more frontal and caudal stimulus presentations. (B)\nResults from multiple flies. The individual traces are the mean left and right\nwing-beat amplitude response taken from 12 individuals. The bold and dotted\nlines represent the mean \u00b1 S.D., respectively, across individuals.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F4\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F4.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Collision-avoidance and landing responses vary with the position of stimulus expansion. (A) The maximum change in value of the wing-beat amplitude (WBA) from the baseline level of both the right (R; red) and left (L; blue) wings varies sinusoidally with the position of the stimulus. (B) A similar variation occurs for the maximum change in the difference between the left and right wing signals. (C) The percentage change in wing-beat frequency (WBF) was largest for expansion occurring in front of the fly and decreases slightly for lateral positions. (D) The probability of eliciting a landing response is greatest for frontal positions. Data points represent the mean value of maximum change \u0026#xB1; S.E.M. The number of trials at each position is different because it was determined by where the fly happened to position the object at the onset of expansion. Data are taken from 300 presentations of a square expanding at a rate of 500\u0026#xB0; s-1 to a single fly.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Collision-avoidance and landing responses vary with the position of stimulus expansion. (A) The maximum change in value of the wing-beat amplitude (WBA) from the baseline level of both the right (R; red) and left (L; blue) wings varies sinusoidally with the position of the stimulus. (B) A similar variation occurs for the maximum change in the difference between the left and right wing signals. (C) The percentage change in wing-beat frequency (WBF) was largest for expansion occurring in front of the fly and decreases slightly for lateral positions. (D) The probability of eliciting a landing response is greatest for frontal positions. Data points represent the mean value of maximum change \u0026#xB1; S.E.M. The number of trials at each position is different because it was determined by where the fly happened to position the object at the onset of expansion. Data are taken from 300 presentations of a square expanding at a rate of 500\u0026#xB0; s-1 to a single fly.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 4.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F4.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 4.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F4.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F4.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 4.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F4.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076123\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 4.\u003C\/span\u003E \n \u003Cp id=\u0022p-19\u0022\u003ECollision-avoidance and landing responses vary with the position of\nstimulus expansion. (A) The maximum change in value of the wing-beat amplitude\n(WBA) from the baseline level of both the right (R; red) and left (L; blue)\nwings varies sinusoidally with the position of the stimulus. (B) A similar\nvariation occurs for the maximum change in the difference between the left and\nright wing signals. (C) The percentage change in wing-beat frequency (WBF) was\nlargest for expansion occurring in front of the fly and decreases slightly for\nlateral positions. (D) The probability of eliciting a landing response is\ngreatest for frontal positions. Data points represent the mean value of\nmaximum change \u00b1 S.E.M. The number of trials at each position is\ndifferent because it was determined by where the fly happened to position the\nobject at the onset of expansion. Data are taken from 300 presentations of a\nsquare expanding at a rate of 500\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E to a single fly.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F5\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F5.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022The effects of expansion rate on collision-avoidance and landing responses. Each column represents the wing-beat amplitude (WBA), and the landing response probabilities plotted against stimulus position as described in Fig. 4 for a different rate of expansion. The functions shown in Fig. 4 were determined for each fly, with each data point representing the mean \u0026#xB1; S.E.M. taken over all the flies. The numbers of flies tested were 8, 11, 11, 8, 12, 11, 8, 10, 7, 7 and 5 for expansion rate in ascending order (starting at 100\u0026#xB0; s-1). The total numbers of stimulus presentations, again in ascending order, were 1945, 2905, 2584, 1746, 3237, 2529, 216, 2223, 1771, 1391 and 1132. The sinusoidal shape of the wing-stroke amplitude responses holds for all expansion rates, with the amplitude of the response being largest for an expansion rate of 1000\u0026#xB0; s-1. The probability of landing is high over the greatest range of positions at an expansion rate of 1430\u0026#xB0; s-1. L, left; R, right; WBF, wing-beat frequency.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;The effects of expansion rate on collision-avoidance and landing responses. Each column represents the wing-beat amplitude (WBA), and the landing response probabilities plotted against stimulus position as described in Fig. 4 for a different rate of expansion. The functions shown in Fig. 4 were determined for each fly, with each data point representing the mean \u0026#xB1; S.E.M. taken over all the flies. The numbers of flies tested were 8, 11, 11, 8, 12, 11, 8, 10, 7, 7 and 5 for expansion rate in ascending order (starting at 100\u0026#xB0; s-1). The total numbers of stimulus presentations, again in ascending order, were 1945, 2905, 2584, 1746, 3237, 2529, 216, 2223, 1771, 1391 and 1132. The sinusoidal shape of the wing-stroke amplitude responses holds for all expansion rates, with the amplitude of the response being largest for an expansion rate of 1000\u0026#xB0; s-1. The probability of landing is high over the greatest range of positions at an expansion rate of 1430\u0026#xB0; s-1. L, left; R, right; WBF, wing-beat frequency.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 5.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F5.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 5.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F5.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F5.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 5.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F5.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076125\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 5.\u003C\/span\u003E \n \u003Cp id=\u0022p-22\u0022\u003EThe effects of expansion rate on collision-avoidance and landing responses.\nEach column represents the wing-beat amplitude (WBA), and the landing response\nprobabilities plotted against stimulus position as described in\n\u003Ca id=\u0022xref-fig-4-4\u0022 class=\u0022xref-fig\u0022 href=\u0022#F4\u0022\u003EFig. 4\u003C\/a\u003E for a different rate of\nexpansion. The functions shown in \u003Ca id=\u0022xref-fig-4-5\u0022 class=\u0022xref-fig\u0022 href=\u0022#F4\u0022\u003EFig.\n4\u003C\/a\u003E were determined for each fly, with each data point representing\nthe mean \u00b1 S.E.M. taken over all the flies. The numbers of flies tested\nwere 8, 11, 11, 8, 12, 11, 8, 10, 7, 7 and 5 for expansion rate in ascending\norder (starting at 100\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E). The total numbers of stimulus\npresentations, again in ascending order, were 1945, 2905, 2584, 1746, 3237,\n2529, 216, 2223, 1771, 1391 and 1132. The sinusoidal shape of the wing-stroke\namplitude responses holds for all expansion rates, with the amplitude of the\nresponse being largest for an expansion rate of 1000\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E. The\nprobability of landing is high over the greatest range of positions at an\nexpansion rate of 1430\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E. L, left; R, right; WBF, wing-beat\nfrequency.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F6\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F6.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Summary of changes in collision-avoidance and landing responses with rate of image expansion. The collision-avoidance response for a given expansion rate (open circles) is the sinusoid amplitude best fitting the maximum change in the difference between wing-beat amplitudes (see Fig. 5, second row), normalized by the maximum mean amplitude. The width of the range of positions for which the probability of landing is greater than 0.5 characterizes the landing response for a given expansion rate (filled circles). This response is normalized by the maximum mean width value. Values are means \u0026#xB1; S.E.M. for each fly.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Summary of changes in collision-avoidance and landing responses with rate of image expansion. The collision-avoidance response for a given expansion rate (open circles) is the sinusoid amplitude best fitting the maximum change in the difference between wing-beat amplitudes (see Fig. 5, second row), normalized by the maximum mean amplitude. The width of the range of positions for which the probability of landing is greater than 0.5 characterizes the landing response for a given expansion rate (filled circles). This response is normalized by the maximum mean width value. Values are means \u0026#xB1; S.E.M. for each fly.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 6.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F6.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 6.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F6.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F6.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 6.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F6.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076127\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 6.\u003C\/span\u003E \n \u003Cp id=\u0022p-24\u0022\u003ESummary of changes in collision-avoidance and landing responses with rate\nof image expansion. The collision-avoidance response for a given expansion\nrate (open circles) is the sinusoid amplitude best fitting the maximum change\nin the difference between wing-beat amplitudes (see\n\u003Ca id=\u0022xref-fig-5-2\u0022 class=\u0022xref-fig\u0022 href=\u0022#F5\u0022\u003EFig. 5\u003C\/a\u003E, second row), normalized\nby the maximum mean amplitude. The width of the range of positions for which\nthe probability of landing is greater than 0.5 characterizes the landing\nresponse for a given expansion rate (filled circles). This response is\nnormalized by the maximum mean width value. Values are means \u00b1 S.E.M.\nfor each fly.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F7\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F7.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Effect of stimulus position and expansion rate on the time course of the wing response. Responses to stimuli presented within \u0026#xB1; 10\u0026#xB0; of the position were pooled. Each trace represents the mean \u0026#xB1; S.D. (shaded area) of the average responses taken from multiple flies. The time course of the responses does not vary with stimulus position but does vary greatly with rate of expansion. The number of flies at each expansion rate is given in Fig. 5. L, left; R, right.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Effect of stimulus position and expansion rate on the time course of the wing response. Responses to stimuli presented within \u0026#xB1; 10\u0026#xB0; of the position were pooled. Each trace represents the mean \u0026#xB1; S.D. (shaded area) of the average responses taken from multiple flies. The time course of the responses does not vary with stimulus position but does vary greatly with rate of expansion. The number of flies at each expansion rate is given in Fig. 5. L, left; R, right.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 7.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F7.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 7.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F7.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F7.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 7.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F7.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076129\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 7.\u003C\/span\u003E \n \u003Cp id=\u0022p-27\u0022\u003EEffect of stimulus position and expansion rate on the time course of the\nwing response. Responses to stimuli presented within \u00b1 10\u00b0 of the\nposition were pooled. Each trace represents the mean \u00b1 S.D. (shaded\narea) of the average responses taken from multiple flies. The time course of\nthe responses does not vary with stimulus position but does vary greatly with\nrate of expansion. The number of flies at each expansion rate is given in\n\u003Ca id=\u0022xref-fig-5-3\u0022 class=\u0022xref-fig\u0022 href=\u0022#F5\u0022\u003EFig. 5\u003C\/a\u003E. L, left; R, right.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F8\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F8.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Collision-avoidance and landing response latencies depend on stimulus position and expansion rate. Latency is measured as the time interval between the onset of image expansion and the initiation of the landing or collision-avoidance response. (A) Latency in response to expansion at a rate of 500\u0026#xB0; s-1 is relatively constant over lateral portions of the fly\u0027s field of view and increases for positions to the front and rear. Data points represent mean latency \u0026#xB1; S.E.M. for 12 flies. (B) Landing response latency to a square expanding at 500\u0026#xB0; s-1 is constant at the stimulus positions at which landing response probability is high. At this expansion rate, the collision-avoidance latency is approximately half that of the landing response. (C) Response latencies plotted as a function of expansion rate. For a given rate of expansion, the minimum of the mean delay functions (such as the two plotted above) was determined. Filled circles represent the minimum mean delay in the landing response, while empty circles represent the minimum mean delay of the collision-avoidance response. The landing response latency decreases with the rate of expansion, whereas for most expansion rates the delay of the collision-avoidance response is constant.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Collision-avoidance and landing response latencies depend on stimulus position and expansion rate. Latency is measured as the time interval between the onset of image expansion and the initiation of the landing or collision-avoidance response. (A) Latency in response to expansion at a rate of 500\u0026#xB0; s-1 is relatively constant over lateral portions of the fly\u0027s field of view and increases for positions to the front and rear. Data points represent mean latency \u0026#xB1; S.E.M. for 12 flies. (B) Landing response latency to a square expanding at 500\u0026#xB0; s-1 is constant at the stimulus positions at which landing response probability is high. At this expansion rate, the collision-avoidance latency is approximately half that of the landing response. (C) Response latencies plotted as a function of expansion rate. For a given rate of expansion, the minimum of the mean delay functions (such as the two plotted above) was determined. Filled circles represent the minimum mean delay in the landing response, while empty circles represent the minimum mean delay of the collision-avoidance response. The landing response latency decreases with the rate of expansion, whereas for most expansion rates the delay of the collision-avoidance response is constant.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 8.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F8.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 8.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F8.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F8.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 8.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F8.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076131\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 8.\u003C\/span\u003E \n \u003Cp id=\u0022p-30\u0022\u003ECollision-avoidance and landing response latencies depend on stimulus\nposition and expansion rate. Latency is measured as the time interval between\nthe onset of image expansion and the initiation of the landing or\ncollision-avoidance response. (A) Latency in response to expansion at a rate\nof 500\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E is relatively constant over lateral portions of the\nfly\u0027s field of view and increases for positions to the front and rear. Data\npoints represent mean latency \u00b1 S.E.M. for 12 flies. (B) Landing\nresponse latency to a square expanding at 500\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E is constant\nat the stimulus positions at which landing response probability is high. At\nthis expansion rate, the collision-avoidance latency is approximately half\nthat of the landing response. (C) Response latencies plotted as a function of\nexpansion rate. For a given rate of expansion, the minimum of the mean delay\nfunctions (such as the two plotted above) was determined. Filled circles\nrepresent the minimum mean delay in the landing response, while empty circles\nrepresent the minimum mean delay of the collision-avoidance response. The\nlanding response latency decreases with the rate of expansion, whereas for\nmost expansion rates the delay of the collision-avoidance response is\nconstant.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F9\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F9.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Open-loop versus closed-loop responses to image expansion. (A) During open-loop presentation the position of the square was controlled externally, as opposed to the closed-loop paradigm in which the fly maintains control over the position of the square. The closed-loop wing responses (filled circles) are repeated from Fig. 4. The open-loop responses (open circles), also generated in response to an expansion at a rate of 500\u0026#xB0; s-1, vary roughly with stimulus position as a square wave, in contrast to the open-loop responses, which vary sinusoidally. Thus, the ability to control the position of the square during the collision-avoidance reaction does affect the amplitude of the response. (B) The probability of landing is slightly reduced for open-loop presentations. (C) The latency of the collision-avoidance response is qualitatively similar for the closed- and open-loop stimuli, with slightly larger latencies in response to open-loop image expansion. (D) The open-loop landing response latencies were qualitatively similar to those seen during closed-loop presentations. Again, the latency is slightly shorter during closed-loop presentations. WBA, wing-beat amplitude.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Open-loop versus closed-loop responses to image expansion. (A) During open-loop presentation the position of the square was controlled externally, as opposed to the closed-loop paradigm in which the fly maintains control over the position of the square. The closed-loop wing responses (filled circles) are repeated from Fig. 4. The open-loop responses (open circles), also generated in response to an expansion at a rate of 500\u0026#xB0; s-1, vary roughly with stimulus position as a square wave, in contrast to the open-loop responses, which vary sinusoidally. Thus, the ability to control the position of the square during the collision-avoidance reaction does affect the amplitude of the response. (B) The probability of landing is slightly reduced for open-loop presentations. (C) The latency of the collision-avoidance response is qualitatively similar for the closed- and open-loop stimuli, with slightly larger latencies in response to open-loop image expansion. (D) The open-loop landing response latencies were qualitatively similar to those seen during closed-loop presentations. Again, the latency is slightly shorter during closed-loop presentations. WBA, wing-beat amplitude.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 9.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F9.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 9.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F9.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F9.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 9.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F9.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076133\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 9.\u003C\/span\u003E \n \u003Cp id=\u0022p-33\u0022\u003EOpen-loop \u003Cem\u003Eversus\u003C\/em\u003E closed-loop responses to image expansion. (A)\nDuring open-loop presentation the position of the square was controlled\nexternally, as opposed to the closed-loop paradigm in which the fly maintains\ncontrol over the position of the square. The closed-loop wing responses\n(filled circles) are repeated from \u003Ca id=\u0022xref-fig-4-6\u0022 class=\u0022xref-fig\u0022 href=\u0022#F4\u0022\u003EFig.\n4\u003C\/a\u003E. The open-loop responses (open circles), also generated in\nresponse to an expansion at a rate of 500\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E, vary roughly\nwith stimulus position as a square wave, in contrast to the open-loop\nresponses, which vary sinusoidally. Thus, the ability to control the position\nof the square during the collision-avoidance reaction does affect the\namplitude of the response. (B) The probability of landing is slightly reduced\nfor open-loop presentations. (C) The latency of the collision-avoidance\nresponse is qualitatively similar for the closed- and open-loop stimuli, with\nslightly larger latencies in response to open-loop image expansion. (D) The\nopen-loop landing response latencies were qualitatively similar to those seen\nduring closed-loop presentations. Again, the latency is slightly shorter\nduring closed-loop presentations. WBA, wing-beat amplitude.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F10\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F10.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Comparison of the time course of responses for closed-loop and open-loop presentations. The changes in wing-beat amplitude (WBA) in response to a square expanding at 500\u0026#xB0; s-1 positioned between -140\u0026#xB0; and -120\u0026#xB0; followed a similar time course for open- and closed-loop presentations. The responses elicited by closed-loop presentation of the square were slightly smaller in magnitude than those in response to open-loop presentations. Closed-loop responses were taken from Fig. 3B; open-loop responses were taken from 5 flies in a manner analogous to the data plots in Fig. 3B.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Comparison of the time course of responses for closed-loop and open-loop presentations. The changes in wing-beat amplitude (WBA) in response to a square expanding at 500\u0026#xB0; s-1 positioned between -140\u0026#xB0; and -120\u0026#xB0; followed a similar time course for open- and closed-loop presentations. The responses elicited by closed-loop presentation of the square were slightly smaller in magnitude than those in response to open-loop presentations. Closed-loop responses were taken from Fig. 3B; open-loop responses were taken from 5 flies in a manner analogous to the data plots in Fig. 3B.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 10.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F10.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 10.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F10.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F10.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 10.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F10.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076115\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 10.\u003C\/span\u003E \n \u003Cp id=\u0022p-35\u0022\u003EComparison of the time course of responses for closed-loop and open-loop\npresentations. The changes in wing-beat amplitude (WBA) in response to a\nsquare expanding at 500\u00b0 s\u003Csup\u003E-1\u003C\/sup\u003E positioned between -140\u00b0 and\n-120\u00b0 followed a similar time course for open- and closed-loop\npresentations. The responses elicited by closed-loop presentation of the\nsquare were slightly smaller in magnitude than those in response to open-loop\npresentations. Closed-loop responses were taken from\n\u003Ca id=\u0022xref-fig-3-3\u0022 class=\u0022xref-fig\u0022 href=\u0022#F3\u0022\u003EFig. 3B\u003C\/a\u003E; open-loop responses\nwere taken from 5 flies in a manner analogous to the data plots in\n\u003Ca id=\u0022xref-fig-3-4\u0022 class=\u0022xref-fig\u0022 href=\u0022#F3\u0022\u003EFig. 3B\u003C\/a\u003E.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003Cli class=\u0022last\u0022\u003E\u003Cdiv class=\u0022element-fig-frag-data clearfix supplementary-material-caption\u0022\u003E\u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022fig-expansion\u0022 id=\u0022F11\u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022highwire-figure\u0022\u003E\u003Cdiv class=\u0022fig-inline-img-wrapper\u0022\u003E\u003Cdiv class=\u0022fig-inline-img\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F11.large.jpg?width=800\u0026amp;height=600\u0026amp;carousel=1\u0022 title=\u0022Model for eliciting collision-avoidance and landing responses. A fly estimates the optic flow experienced during flight using a two-dimensional array of motion detectors (i). Local motion information is then spatially pooled such that the image expansion in both the lateral and frontal fields of view is calculated (ii). The outputs of each of these three expansion calculations are then temporally integrated (iii) and passed through a threshold detector (iv). Expansion detected in a lateral field of view triggers a collision-avoidance response in the opposite direction, while frontal image expansion causes a landing response (v). Lateral expansion on one side inhibits the opposite expansion pathway, preventing a saccade from being immediately followed by another saccade in the opposite direction.\u0022 class=\u0022highwire-fragment fragment-images colorbox-load\u0022 rel=\u0022gallery-fragment-images-1254005668\u0022 data-figure-caption=\u0022\u0026lt;div class=\u0026quot;highwire-markup\u0026quot;\u0026gt;Model for eliciting collision-avoidance and landing responses. A fly estimates the optic flow experienced during flight using a two-dimensional array of motion detectors (i). Local motion information is then spatially pooled such that the image expansion in both the lateral and frontal fields of view is calculated (ii). The outputs of each of these three expansion calculations are then temporally integrated (iii) and passed through a threshold detector (iv). Expansion detected in a lateral field of view triggers a collision-avoidance response in the opposite direction, while frontal image expansion causes a landing response (v). Lateral expansion on one side inhibits the opposite expansion pathway, preventing a saccade from being immediately followed by another saccade in the opposite direction.\u0026lt;\/div\u0026gt;\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cspan class=\u0022hw-responsive-img\u0022\u003E\u003Cimg class=\u0022highwire-fragment fragment-image lazyload\u0022 alt=\u0022Fig. 11.\u0022 src=\u0022data:image\/gif;base64,R0lGODlhAQABAIAAAAAAAP\/\/\/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\u0022 data-src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F11.medium.gif\u0022\/\u003E\u003Cnoscript\u003E\u003Cimg class=\u0022highwire-fragment fragment-image\u0022 alt=\u0022Fig. 11.\u0022 src=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F11.medium.gif\u0022\/\u003E\u003C\/noscript\u003E\u003C\/span\u003E\u003C\/a\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cul class=\u0022highwire-figure-links inline\u0022\u003E\u003Cli class=\u0022download-fig first\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F11.large.jpg?download=true\u0022 class=\u0022highwire-figure-link highwire-figure-link-download\u0022 title=\u0022Download Fig. 11.\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload figure\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022new-tab\u0022\u003E\u003Ca href=\u0022https:\/\/jeb.biologists.org\/content\/jexbio\/205\/18\/2785\/F11.large.jpg\u0022 class=\u0022highwire-figure-link highwire-figure-link-newtab\u0022 target=\u0022_blank\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EOpen in new tab\u003C\/a\u003E\u003C\/li\u003E\u003Cli class=\u0022download-ppt last\u0022\u003E\u003Ca href=\u0022\/highwire\/powerpoint\/1076117\u0022 class=\u0022highwire-figure-link highwire-figure-link-ppt\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EDownload powerpoint\u003C\/a\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003Cdiv class=\u0022fig-caption\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cspan class=\u0022fig-label\u0022\u003EFig. 11.\u003C\/span\u003E \n \u003Cp id=\u0022p-45\u0022\u003EModel for eliciting collision-avoidance and landing responses. A fly\nestimates the optic flow experienced during flight using a two-dimensional\narray of motion detectors (i). Local motion information is then spatially\npooled such that the image expansion in both the lateral and frontal fields of\nview is calculated (ii). The outputs of each of these three expansion\ncalculations are then temporally integrated (iii) and passed through a\nthreshold detector (iv). Expansion detected in a lateral field of view\ntriggers a collision-avoidance response in the opposite direction, while\nfrontal image expansion causes a landing response (v). Lateral expansion on\none side inhibits the opposite expansion pathway, preventing a saccade from\nbeing immediately followed by another saccade in the opposite direction.\u003C\/p\u003E\n \u003Cdiv class=\u0022sb-div caption-clear\u0022\u003E\u003C\/div\u003E\u003C\/div\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003C\/ul\u003E\u003C\/div\u003E\u003C\/div\u003E\u003C\/div\u003E \u003C\/div\u003E\n\n \n \u003C\/div\u003E\n\u003Cdiv class=\u0022panel-separator\u0022\u003E\u003C\/div\u003E\u003Cdiv class=\u0022panel-pane pane-earthchem\u0022 \u003E\n \n \n \n \u003Cdiv class=\u0022pane-content\u0022\u003E\n \u003Ca href=\u0022http:\/\/ecp.iedadata.org\/doidata\/\u0022 class=\u0022\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003E\u003Cimg src=\u0022http:\/\/ecp.iedadata.org\/doibanner\/\u0022 alt=\u0022\u0022 \/\u003E\u003C\/a\u003E \u003C\/div\u003E\n\n \n \u003C\/div\u003E\n\u003C\/div\u003E\n \u003C\/div\u003E\n\u003C\/div\u003E\n\u003C\/div\u003E\u003Cscript type=\u0022text\/javascript\u0022 src=\u0022https:\/\/jeb.biologists.org\/sites\/default\/files\/js\/js_hZg96SP9gBcOluDp2mGc57d8sP8uJ7g8P_JYsCISOgQ.js\u0022\u003E\u003C\/script\u003E\n\u003C\/body\u003E\u003C\/html\u003E"}